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UNIVERSITY OF CALIFORNIA Agricultural experiment Station 

College of Agriculture e. w. hilgard. director 

BERKELEY, CALIFORNIA 



CIRCULAR No. 4. 

(June, 1903.) 



ANTHRAX 

By ARCHIBALD R. WARD, 

Veterinarian and Bacteriologist. 



Synonyms. — Anthrax is also known by the following names: Charbon, 
Splenic fever, Splenic apoplexy, Malignant carbuncle, Malignant pus- 
tule, Woolsorters' disease. 

Animals Affected. — The disease attracts attention chiefly as a cattle 
disease, but it may be contracted by man and most of the domestic 
animals, such as horses, sheep, swine, and dogs. 

Conditions Under Which the Disease is Liable to Break Out. — Anthrax 
is caused by the presence of bacteria in the blood, which generally gain 
access to the body from the soil with the food. Anthrax germs thrive 
and exist indefinitely in damp, heavy, undrained swampy land having a 
high water-table or subject to periodical flooding. River-bottom land, 
dried lake basins, or deltas are characteristic of the localities infected with 
anthrax. The disease is most apt to occur during hot, dry weather. 
At such times cattle are frequently pastured upon low lands which may 
not be desirable nor available for use in the winter. In Louisiana the 
disease is spread by the bite of large flies, causing swellings and sores 
on the skin. 

Symptoms. — The disease kills very quickly, sometimes in only a few 
hours after sickness is noticed. There is high fever with the accom- 
panying quickened breathing, hot horns and ears. Great variation in 
behavior is noted in different affected animals. Sometimes there is 
nervous excitement; sometimes great depression. The urine may be 
dark and the dung may be bloody or streaked with blood. The nostrils, 
tongue, etc., may be darkened in color. In some cases the disease affects 
the skin, producing swellings that do not crackle when touched. 



— 2 — 

Pigs affected by eating infected meat generally contract the disease 
in the throat and intestines. There is marked swelling of the throat, 
interfering with breathing; diarrhea and a darkened color of the tongue. 

In man the disease occurs first as a malignant carbuncle, generally 
traced to some slight wound, incurred while skinning an infected 
carcass. Later there may be great swelling of the affected part, with 
possible fatal termination. 

Post-Mortem Appearances. — The blood is usually dark in color and 
tarry in consistency. The spleen (milt) is always distended with a 
bloody, pulpy mass. There is frequently found under the skin, and 
around some of the internal organs, a gelatinous, yellowish, transparent 
substance, which may be streaked with blood. It is exceedingly dan- 
gerous to tamper with the carcass of an animal dead of anthrax, unless 
the hands are protected by rubber gloves. 

Disposal of the Dead. — Burning is the most desirable means of dis- 
posal. If burial is necessary it is exceedingly desirable that the carcasses 
of animals dead of anthrax be buried without being open to the air for 
any length of time. A spot should be selected in a locality where there 
is no danger of contaminating a stream of water. Animals grazing over 
the grave, years after burial, are liable to contract the disease. Sur- 
rounding the carcass with lime is desirable. Hogs will die if fed with 
the carcasses of animals dead of anthrax. 

Differences Between Anthrax and Texas Fever. — To the untrained 
observer there are some similarities in the symptoms and internal 
alterations of Texas fever and anthrax, and in consequence some con- 
fusion exists. In both cases there is fever and there may be dark-colored 
urine. In both the spleen is enlarged. Here the identity ceases. 
Below are tabulated some of the more prominent differences between 
them (From Law, Veterinary Medicine, Vol. 4): 



Texas Fever. 
Not restricted to swampy lands only. 



Attacks bovine animals only. 

Sucking calves nearly immune. 

Mucosae become increasingly pale ; yellow 
in violent attacks. 

Blood becomes increasingly tbin and watery. 

Bile abundant, tbick and tarry. 



Anthrax. 
Prevails in ricb, swampy, impermeable 
soils ; not permanently implanted on 
open, well-drained land. 

Attacks mammals, generally, especially 
berbivora. 

Sucking calves susceptible. 

Mucosae dusky brownisb red ; not pallid nor 
yellow. 

Blood becomes tbick, tarry, not watery. 

Bile fluid. 



It is an unfortunate fact that information concerning Texas fever has 
not been sufficiently disseminated among stockmen, which has resulted 
in undesirable confusion. The present writer holds the belief that 



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many cases of Texas fever in the past have been called anthrax, and 
that future investigations will show the regions infected with anthrax to 
be much more restricted than is now generally believed to be the case. 

Vaccination for Anthrax. — There is on the market a vaccine by which 
it is claimed a mild attack of anthrax may be induced, with the result 
that the animal is protected from a natural attack. Its use is much more 
dangerous than the common practice of vaccinating for blackleg, and 
vaccination for anthrax should be practiced only with great caution. 
There is need of its use only upon animals actually pastured upon 
swampy lands, which are known beyond a doubt to be infected with 
anthrax. Do not vaccinate for anthrax merely because its outbreak is 
dreaded, for some risk of actually introducing the disease is incurred 
thereby. Anthrax originates in animals pastured on low, swampy land 
and is not usually immediately communicated to other animals from 
them unless there are carbuncles present on the surface of the body. 
Animals may contract the disease on infected ground, and the disease 
break out after they have been driven elsewhere and mixed with other 
cattle, without the others contracting the disease. 

Anthrax is an entirely different disease from blackleg, and conse- 
quently blackleg vaccine is useless for preventing anthrax, and vice versa. 

Treatment Unsatisfactory. — Anthrax does not usually yield to medici- 
nal treatment. 



SACRAMENTO '. 
W. SHANNON, • - SUPT. STATE PRINTING. 
1903.